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Turbulence Production and Relaxation in Bowl-in-Piston Engines
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Abstract
In order to generate turbulence and thereby improve fuel-air mixing and combustion, direct-injection engines often incorporate high-squish piston bowls and intake-generated air swirl. Here, laser-velocimetry measurements of turbulent air motion in a motored direct-injection engine are examined with power-spectral analysis and with conventional and filtered ensemble-averaging techniques. Results from cylindrical and square piston bowls are interpreted in the context of conventional eddy-cascade concepts of turbulence. In particular, the results show that after intake, as the velocity fluctuations decrease in intensity, their power spectrum (frequency distribution) E(f ) relaxes toward the canonical ƒ-5/3 form associated with stationary, homogeneous turbulence in the inertial subrange. During the turbulence-production period around compression TDC, however, the power spectrum exhibits increased high-frequency content and (in the square bowl) anisotropy.
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Fansler, T., "Turbulence Production and Relaxation in Bowl-in-Piston Engines," SAE Technical Paper 930479, 1993, https://doi.org/10.4271/930479.Also In
References
- Arcoumanis C. Whitelaw J. H. “Fluid Mechanics of Internal Combustion Engines - A Review.” Proc. I. Mech. E. 201C 57 74 1987
- Komiyama, K. Kajiyama Okada M. Investigation and Development of a Turbulent Open Combustion Chamber SAE Paper 800967 1980
- Kihara R. Mikami Y. Kinbara M. The Advantages of the Isuzu Square Combustion Chamber for D.I. Engines SAE Paper 830372 1983
- Vafidis C. “Influence of Induction Swirl and Piston Configuration on Air Flow in a Four-Stroke Model Engine.” Proc. I. Mech. E. 198C 71 79 1984
- Shimoda M. Shigemori M. Tsuruoka S. Effect of Combustion Chamber Configuration on In-Cylinder Air Motion and Combustion Characteristics of D.I. Diesel Engine SAE Paper 850070 1985
- Wakisaka T. Shimamoto Y. Isshiki Y. Three-Dimensional Numerical Analysis of In-Cylinder Flows in Reciprocating Engines SAE Paper 860464 1986
- Bertoli C. Corcione F. E. Police G. Valentino G. Effect of Combustion Chamber Shape on Air Flow Field in a D.I. Diesel Engine SAE Paper 870338 1987
- Fansler T. D. French D. T. Swirl, Squish and Turbulence in Stratified-Charge Engines: Laser-Velocimetry Measurements and Implications for Combustion SAE Paper 870371 1987
- Iijima T. Bracco F. V. LDV Measurements in an Engine with Square and Circular Piston Cups SAE Paper 872073 1987
- Fansler T. D. French D. T. Cycle-Resolved Laser-Velocimetry Measurements in a Reentrant-Bowl-Piston Engine SAE Paper 880377 1988
- Diwakar R. Krieger R. B. Meintjes K. Groff E. G. “Engine and High Turbulence Piston Therefor,” Sept. 11 1990 General Motors Corporation Detroit, MI
- Rask R. B. “Comparison of Window, Smoothed-Ensemble, and Cycle-by-Cycle Data-Reduction Techniques for Laser-Doppler Anemometer Measurements of In-Cylinder Velocity.” Morel T. Lohmann R. P. Rackley J. M. Fluid Mechanics of Combustion Systems ASME New York 1981
- Liou T.-M. Santavicca D. A. “Cycle Resolved LDV Measurements in a Motored IC Engine.” Trans. ASME: J. Fluids Eng. 107 232 240 1985
- Enotiadis A. C. Vafidis C. Whitelaw J. H. “Interpretation of Cyclic Flow Variations in Motored Internal Combustion Engines.” Expts. in Fluids 10 77 86 1990
- Catania A. E. Dongiovanni C. Mittica A. Time-Frequency Spectral Structure of Turbulence in an Automotive Engine SAE Paper 920153 1992
- Lancaster D. R. “Effects of Engine Variables on Turbulence in a Spark-Ignition Engine.” SAE Transactions 85 671 688 1976
- Saxena V. Rask R. B. Influence of Inlet Flows on the Flow Field in an Engine SAE Paper 870369 1987
- Le Coz J. Henriot S. Pinchon P. An Experimental and Computational Analysis of the Flow Field in in a Four- Valve Spark-Ignition Engine - Focus on Cycle Resolved Turbulence SAE Paper 900056 1990
- Arcoumanis C. Enotiadis A. C. Whitelaw J. H. “Frequency Analysis of Tumble and Swirl in Motored Engines.” Proc. I. Mech. E. 205D 177 184 1991
- Fansler T. D. Laser-Velocimetry Measurements of Swirl and Squish Flows in an Engine with a Cylindrical Piston Bowl SAE Paper 850124 1985
- Fansler T. D. “Photon-Correlation Laser Velocimetry in Reciprocating- Engine Research.” Abbiss J. B. Smart A. E. Photon Correlation Techniques and Applications Opt. Soc. Amer. Conf. Proc. Ser. 1 1988
- Bendat J. S. Piersol A. G. Random Data: Analysis and Measurement Procedures Wiley-Interscience New York 2nd 1986
- Press W. H. Flannery B. P. Teukolsky S. A. Vetterling W. T. Numerical Recipes: The Art of Scientific Computing Cambridge Univ. Press New York 1986
- Bradley D. Hynes J. Lawes M. Sheppard C. G. W. Limitations to Turbulence-Enhanced Burning Rates in Lean Burn Engines I. Mech. E. Conf. on Combustion in Engines - Technology and Applications, Paper C46/88 1988
- Tennekes H. Lumley J. L. A First Course in Turbulence MIT Press Cambridge, MA 1972
- Townsend A. The Structure of Turbulent Shear Flow Cambridge Univ. Press Cambridge, UK 2nd 1976
- Reuss D. L. Adrian R. J. Landreth C. C. French D. T. Fansler T. D. Instantaneous Planar Measurements of Velocity and Large-Scale Vorticity and Strain Rate in an Engine Using Particle-Image Velocimetry SAE Paper 890616 1989
- Fraser R. A. Bracco F. V. Cycle-Resolved LDV Integral Length-Scale Measurements in an I. C. Engine SAE Paper 880021 1988
- Glover A. R. Hundleby G. E. Hadded O. The Development of Scanning LDA for the Measurement of Turbulence in Engines SAE Paper 880378 1988
- Glover A. R. Hundleby G. E. Hadded O. An Investigation into Engine Turbulence Using Scanning LDA SAE Paper 880379 1988
- Yeung P. K. Brasseur J. G. “The Response of Isotropic Turbulence to Isotropic and Anisotropic Forcing at the Large Scales.” Phys. Fluids A 3 884 897 1991